Conservation groups met Thursday to call on the Trump administration to halt oil and gas drilling permits and cancel lease sales being developed during the government shutdown, saying they violate federal law.
Auctions scheduled in February and March span six states and 2.3 million acres of public lands.
It is the largest quarterly lease sales in at least a decade.
The groups sent a letter to acting Interior Secretary David Bernhardt, saying that issuing drilling permits during the shutdown violates the National Environmental Policy Act and Federal Land Policy and Management Act.
The letter goes on to say issuing drilling permits during the shutdown also violates the Antideficiency Act, which prohibits work without pay in the absence of congressional appropriations.